IPAC2018 - List of Authors (Kurennoy, S.S.)

Paper	Title	Page
TUPAL035	3D Beam Dynamics Modeling of MEBT for the New LANSCE RFQ Injector	1081
	S.S. Kurennoy LANL, Los Alamos, New Mexico, USA
	The new RFQ-based proton injector at LANSCE requires a specialized medium-energy beam transfer (MEBT) after the RFQ at 750 keV due to a following long (~3 m) existing common transfer line that also serves for transporting negative-ion beams to the DTL entrance. The horizontal space for MEBT elements is limited because two beam lines merge at 18-degree angle. The MEBT design developed with envelope codes includes two compact quarter-wave RF bunchers and four short quadrupoles with steerers, all within the length of about 1 m. The beam size in the MEBT is large, comparable to the beam-pipe aperture, hence non-linear 3D field effects at large radii become important. Using CST Studio codes, we calculate buncher RF fields and quadrupole magnetic fields and use them to perform particle-in-cell beam dynamics modeling of MEBT with realistic beam distributions from the RFQ. Our results indicate a significant emittance growth not predicted by standard beam dynamics codes. Its origin was traced mainly to the quadrupole edge fields. Quadrupole design modifications are proposed to improve the MEBT performance.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-TUPAL035
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Paper

Title

Page

3D Beam Dynamics Modeling of MEBT for the New LANSCE RFQ Injector

1081

S.S. Kurennoy
LANL, Los Alamos, New Mexico, USA

The new RFQ-based proton injector at LANSCE requires a specialized medium-energy beam transfer (MEBT) after the RFQ at 750 keV due to a following long (~3 m) existing common transfer line that also serves for transporting negative-ion beams to the DTL entrance. The horizontal space for MEBT elements is limited because two beam lines merge at 18-degree angle. The MEBT design developed with envelope codes includes two compact quarter-wave RF bunchers and four short quadrupoles with steerers, all within the length of about 1 m. The beam size in the MEBT is large, comparable to the beam-pipe aperture, hence non-linear 3D field effects at large radii become important. Using CST Studio codes, we calculate buncher RF fields and quadrupole magnetic fields and use them to perform particle-in-cell beam dynamics modeling of MEBT with realistic beam distributions from the RFQ. Our results indicate a significant emittance growth not predicted by standard beam dynamics codes. Its origin was traced mainly to the quadrupole edge fields. Quadrupole design modifications are proposed to improve the MEBT performance.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-TUPAL035

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)